The present invention concerns repair of automotive radiators and more particularly concerns a method and an apparatus for recoring radiators.
In the course of repairing such radiators a recoring is often found to be necessary in which the tube-and-fin "core" of the radiator is removed from the top and bottom tanks. Conventional radiator construction includes a tank joined to the core by means of a header which receives the core tubes and forms the bottom of the tank when the tank is mounted within the header. The most common radiator construction currently employed includes a brass tank which is soldered to the header. In recoring the radiator, the soldered joint is loosened for removal of the tank. Upon completion of the recoring, the tank is placed into the header and the solder connection rerun.
Recently there has developed a trend towards replacement of the brass tank with a plastic tank mechanically joined to the header. The plastic tank is positioned against a gasket received in a header recess. A tank flange is compressed against the gasket and secured in position with a series of tabs formed integrally with the header, which are bent down to retain the tank compressed against the gasket.
Radiator repair shops have, for the most part, relied on impromptu fixturing for conducting these operations.
Reassembly of the brass tank to the header has often involved difficulties due to deformation of the tank bottom or slight irregularities in the header recess receiving the tank lip, such that the application of pressure is necessary in order to get the tank to properly seat. In addition, there sometimes exists excessive clearance between the tank lip and the header tank recess, in turn resulting in a weaker solder joint. The handling of the disassembly and reassembly of the tank and radiator core and header is relatively difficult and slows completion of the recoring.
Plastic tank designs have presented their own peculiar problems in recoring, particularly in crimping and decrimping of the tabs while properly insuring a seal of the tank bottom against the gasket and the header.
The crimped tabs are difficult to loosen because they are often jammed tightly into the plastic tank, with minimal clearance between the tank side wall and the tab end, making it difficult to obtain insertion of a tool for decrimping. The compression of the tank against the gasket further aggravates the problem due to the tightness with which the tabs are forced against the tank flange.
To obtain a proper seal between the header and tank is also troublesome since, if the header recess receiving the gasket is deformed, leakage will often occur. Such deforming can be inflicted by the decrimping operation or the subsequent crimping operation due to pressure exerted by hand tools on the outer edge of the header.
In addition, the entire tank crimping and decrimping operations are relatively time consuming, thereby increasing the cost of labor to recore.
Previous attempts at improving the above described fixture assemblies and fixturing methods have generally not alleviated the time problem and involve relatively costly fixturing which has not successfully speeded up the disassembly or assembly steps. It has also not satisfactorily handled the problem of insuring leak free connections from the tank to the header.
In addition, the radiator repair industry is faced with the task of being prepared to repair and recore efficiently both the conventional brass tank and the newer plastic tank radiator.
Such plastic tanks are, in the United States, only now beginning to exist in commercially relevant quantities, but ultimately may account for much of radiator repairs.
In the interim period, both types of radiators will necessarily need to be accommodated. The necessary fixturing apparatus is relatively costly, and represents a sizable capital investment for businesses having limited financial resources, such as the typical radiator repair shop. It is, therefore, important that any fixturing apparatus intended for that application be adaptable to both tank mounting styles.
The decrimping and crimping tools heretofore employed have either been conventional hand tools, such as vise grips pressed into service for this purpose, or have been specially designed pneumatic tools. In the case of the conventional hand tools, these do not efficiently perform the crimping and decrimping operations and, therefore, require excessive labor. The conventional pneumatic tools, on the other hand, are relatively difficult to control and often apply excessive force to the tab, due to a lack of "feel" associated with their manipulation.
Accordingly, it is an object of the present invention to provide a fixturing apparatus and method for the recoring of radiators which is adaptable to both conventional and plastic tank construction and which further is adaptable to the wide variety of radiator tank sizes and configurations that exist, such that a simple universal fixture can be employed in recoring radiators of all types.
A further object of the present invention is to provide such a fixturing apparatus and method which greatly facilitates the recoring operation of radiators of both metal and plastic tank construction.
It is still another object of the present invention to provide decrimping and crimping hand tools for use with the fixturing apparatus and method in order to efficiently and rapidly conduct the crimping and decrimping steps incidental to recoring of the plastic tanks.